Tri / Triathlon / Triathlons - do they float your boat?

Beta firmware (6.13) for Forerunner 920xt which adds:-

"
Changes made from version 6.11 to 6.13:

• Added support for the latest running dynamics. These include: Ground Contact Time Balance, Stride Length, and Vertical Ratio (requires a new HRM-Run, the original HRM-Run with sw ver 6.60, or HRM-Tri with sw ver 4.20).
  
  

Changes made from version 6.10 to 6.11:

• Restored the version of the pool swim distance algorithm that was present in the 5.25 beta. This will improve distance accuracy for the users having problems with released software versions. We will continue to work on improving the pool swim algorithm in future betas.
  "
  
  

https://www8.garmin.com/support/download_details.jsp?id=7627

Given Garmin's problems with GA firmware quality I'll skip the beta this time, plus it doesn't give me anything until I get a working HRM-Tri from Garmin.